American politicians can be bought off very cheaply by corporations, but the minute people try to crowd-fund bribes to get actual representation in government corporations will just start to offer more. Some companies and industries have more wealth than entire nations at their disposal. If it comes down to a bidding war between you and Google you will lose. If paying out a little more to congressmen will keep an industry making even greater profits they'll do it.
The only real fix is actual accountability for lawmakers. It means massive amounts of oversight to catch those who accept bribes in any forms (including "campaign contributions") and it means making it simple for the people to vote out anyone who refuses to represent their interests.
Right now, bribery is effectively legal, there is zero accountability and between the two party system, gerrymandering, and voter suppression even if you manage to get someone out of office you're probably not going to like the person you're forced to vote in to replace them. We're a very long way from fixing the problem and all of the people in power have zero incentive to start getting us there because they profit off the system being broken.
A neat solution is actually public campaign financing. We currently say that you can give $3 towards public financing on your tax return when you file - why not make that $100?
Collectively, people have a lot more money than corporations do - the trouble is organization. But basically flooding the system with so much money that corporate bribery becomes insignificant is the other option to banning it
It’s too late. Citizens United means corporations and the ueber-wealthy can do whatever they want. McCain-Feingold represented actual progress in this area, and it’s gone now. We are going to witness heavy fascism in the US, and I wish I knew what to do about it. Other than somehow prevent Peter Thiel from escaping to New Zealand, since it’s partially his fault and he should have to reap what he sowed.
(Tangentially, Feingold was one of the smartest people in the Senate. Wisconsin voted him out in favor of Johnson, one of the stupidest people in the Senate — the only thing that keeps him from the top spot is just the fuckload of really dumb other Republican senators.)
This has actually been done rather often in the past, you can start a donor driven PAC that can compete with corporate lobbyists with crowdfunding. It's generally quite a bit cheaper too because while we all love to criticize politicians for only listening to monied interests if they can raise some campaign funds and get brownie points for their voting base they're happy to dramatically spurn the corporate funding they'd otherwise accept with open arms.
Honestly though, actually reaching out to your representatives and talking to them is far more effective than most people assume.